Various processes are known for manufacturing micro-electro-mechanical structures, such as micro motors or micro-actuators that can be used for fine position control of reading and writing heads in hard-disk drives.
In particular, in more recent times, to prevent burdensome steps for removing buried sacrificial layers, it has been proposed to use two distinct semiconductor wafers: a first wafer is designed to house the microstructures, while a second wafer operates as a support for the microstructures and integrates the control circuits of the microstructures.
EP-A-1 151 962, which is incorporated by reference describes a manufacturing process of the above-referred type, which uses integrated silicon plugs for electrically connecting the second wafer to the front of the first wafer, on which the electrical interconnections are formed. The rear of the wafer is, instead, fixed to a protective cap, a read/write head or a further wafer.
The above known solution, albeit representing a considerable improvement over previous solutions, is still complex and entails high manufacturing costs.
Therefore, a need has arisen for a micro-electro-mechanical device and the manufacturing process thereof which overcomes the disadvantages referred to above.